Practice Guidelines for Perioperative Transesophageal Echocardiography

* Developed by the American Society of Anesthesiologists Task Force on Perioperative Transesophageal Echocardiography: Daniel M. Thys, M.D., Chair, New York, New York; Martin D. Abel, M.B.B.Ch., Rochester, Minnesota; Robert F. Brooker, M.D., Wausau, Wisconsin; Michael K. Cahalan, M.D., Salt Lake City, Utah; Richard T. Connis, Ph.D., Woodinville, Washington; Peggy G. Duke, M.D., Atlanta, Georgia; David G. Nickinovich, Ph.D., Bellevue, Washington; Scott T. Reeves, M.D., Charleston, South Carolina; Marc A. Rozner, Ph.D., M.D., Houston, Texas; Isobel A. Russell, M.D., San Francisco, California; Scott C. Streckenbach, M.D., Boston, Massachusetts; Pamela Sears-Rogan, M.D., Washington, DC (American Society of Echocardiography); and William J. Stewart, M.D., Cleveland, Ohio (American College of Cardiology).PRACTICE Guidelines are systematically developed recommendations that assist the practitioner and the patient in making decisions about health care. These recommendations may be adopted, modified, or rejected according to clinical needs and constraints and are not intended to replace local institutional policies. In addition, Practice Guidelines developed by the American Society of Anesthesiologists (ASA) are not intended as standards or absolute requirements, and their use cannot guarantee any specific outcome. Practice Guidelines are subject to revision as warranted by the evolution of medical knowledge, technology, and practice. They provide basic recommendations that are supported by a synthesis and analysis of the current literature, expert and practitioner opinion, open forum commentary, and clinical feasibility data.This update includes data published since the Practice Guidelines for Perioperative Transesophageal Echocardiography were adopted by the ASA and the Society of Cardiovascular Anesthesiologists in 1995 and published in 1996.1For these Guidelines, perioperative transesophageal echocardiography (TEE) refers to TEE performed on surgical patients before, during, or immediately after surgery, including the critical care setting. Evidence of effectiveness is discussed relative to specific settings where perioperative TEE is customarily used (e.g. , cardiac surgery, noncardiac surgery, and critical care).The purposes of these Guidelines are (1) to assist the physician in determining the appropriate application of TEE and (2) to improve the outcomes of surgical patients by defining the utility of perioperative TEE based on the strength of supporting evidence.These Guidelines focus on the application of TEE in surgical patients and potential surgical patients in the setting of cardiac surgery, noncardiac surgery, and postoperative critical care. The Guidelines do not apply to the assessment of nonsurgical patients or to postdischarge follow-up assessment of surgical patients.The Task Force believes that physician proficiency in the use of perioperative TEE is of paramount importance due to the risk of adverse outcomes resulting from incorrect interpretation. The Guidelines do not address training, certification, credentialing, and quality assurance, which are addressed elsewhere.2–5These Guidelines are intended for anesthesiologists and other physicians (e.g. , cardiologists, surgeons, and intensivists) who use TEE in the perioperative setting. Recommen- dations to perform TEE are not applicable when the procedure cannot be performed properly or safely nor do they apply when TEE equipment or skilled examiners are unavailable. The recommendations in this report are based on consideration of the risk benefit ratio for individual patients.The ASA and Society of Cardiovascular Anesthesiologists jointly appointed a task force of 13 members, including anesthesiologists in both private and academic practice from various geographic areas of the United States, two cardiologists (one representing the American College of Cardiology and the other representing the American Society of Echocardiography), and two consulting methodologists from the ASA Committee on Standards and Practice Parameters.The Task Force developed the Guidelines by means of a seven-step process. First, they reached consensus on the criteria for evidence. Second, original published research studies from peer-reviewed journals relevant to TEE were reviewed and evaluated. Third, expert consultants were asked (1) to participate in opinion surveys on the effectiveness of TEE imaging and (2) to review and comment on a draft of the Guidelines developed by the Task Force. Fourth, opinions about the Guidelines recommendations were solicited from a sample of active members of the ASA who personally perform TEE as a part of their practice. Fifth, the Task Force held an open forum at a major international meeting†to solicit input on its draft recommendations. Sixth, the consultants were surveyed to assess their opinions on the feasibility of implementing the Guidelines. Seventh, all available information was used to build consensus within the Task Force to finalize the Guidelines (appendix 1).Preparation of these Guidelines followed a rigorous methodologic process (appendix 2). Evidence was obtained from two principal sources: scientific evidence and opinion-based evidence.Study findings from scientific literature published after 1994 (not excluding sentinel articles published prior to 1994) were aggregated and reported in summary form by evidence category, as described later. All literature (e.g. , randomized controlled trials, observational studies, and case reports) relevant to each topic was considered when evaluating the findings. For reporting purposes in this document, only the highest level of evidence (i.e. , levels 1, 2, or 3 identified below) within each category (i.e. , A, B, or C) is included in the summary.Randomized controlled trials report statistically significant (P < 0.01) differences between clinical interventions for a specified clinical outcome.Information from observational studies permits inference of beneficial or harmful relationships among clinical interventions and clinical outcomes.The literature cannot determine whether there are beneficial or harmful relationships among clinical interventions and clinical outcomes.The lack of scientific evidence in the literature is described by the following conditions.All opinion-based evidence relevant to each topic (e.g. , survey data, open-forum testimony, Internet-based comments, letters, and editorials) was considered in the development of these Guidelines. However, only the findings obtained from formal surveys are reported.Opinion surveys were developed by the Task Force to address each clinical intervention identified in the document. Identical surveys were distributed to two groups of respondents: expert consultants and ASA members.Survey responses from Task Force–appointed expert consultants are reported in summary form in the text. A complete listing of consultant survey responses is reported in a table in appendix 2.Survey responses from a sample of members of the ASA are reported in summary form in the text. A complete listing of ASA member survey responses is reported in a table in appendix 2.Expert consultant and ASA membership survey responses are recorded using a 5-point scale and summarized based on median values.§Open-forum testimony, Internet-based comments, letters, and editorials are all informally evaluated and discussed during the development of Guidelines recommendations. When warranted, the Task Force may add educational information or cautionary notes based on this information.Cardiac and thoracic aortic procedures consist of cardiac and thoracic aortic surgery, and catheter-based intracardiac procedures.Cardiac and thoracic aortic surgery: For cardiac or thoracic aortic surgery patients, the literature reports variations in sensitivity, specificity, or positive and negative predictive values for the detection of abnormalities relating to valvular, coronary, aortic, congenital, and other cardiovascular disease (table 1in appendix 2). Examples of these abnormalities include mitral valve abnormalities, valvular abscesses, myocardial ischemia, aortic dissection, and atrial septal defect (Category B2 evidence ). The literature also reports a range of sensitivity, specificity, and positive and negative predictive values for the confirmation or refinement by TEE of the preoperative diagnosis (table 1in appendix 2). Examples include aortic dissection, aortic intramural hemorrhage, and valvular or mural infective endocarditis lesions (Category B2 evidence ). The ASA members agree and the consultants strongly agree that TEE should be used for all cardiac or thoracic aortic surgery patients.For adult patients without contraindications, TEE should be used in all open heart (e.g. , valvular procedures) and thoracic aortic surgical procedures and should be considered in coronary artery bypass graft surgeries to: (1) confirm and refine the preoperative diagnosis, (2) detect new or unsuspected pathology, (3) adjust the anesthetic and surgical plan accordingly, and (4) assess the results of surgical intervention. In small children, the use of TEE should be considered on a case-by-case basis because of risks unique to these patients (e.g. , bronchial obstruction).Catheter-based intracardiac procedures: Studies with observational findings confirm the utility of TEE or intracardiac echocardiography for guiding management of catheter-based intracardiac procedures (e.g. , occluder device placement, percutaneous valvular procedures, and intracardiac ablation procedures) (Category B2 evidence ). In addition, studies with observational findings report the detection of unsuspected abnormalities by TEE, such as aortic root abscess, atrial thrombi, atrial septal aneurysm, shunting, mitral valve/annular calcification and regurgitation, wall motion abnormalities, and tamponade (Category B2 evidence ). The detection of pericardial effusion is also reported (Category B3 evidence ).Both the consultants and ASA members agree that TEE should be used for patients undergoing transcatheter intracardiac procedures when general anesthesia is provided and intracardiac ultrasound is not used. The ASA members agree and the consultants strongly agree that TEE should be used for septal defect closure or atrial appendage obliteration. Both the consultants and ASA members strongly agree that TEE should be used during catheter-based valve replacement and repair. Finally, both the consultants and ASA members are equivocal regarding the use of TEE during dysrhythmia treatment.For patients undergoing transcatheter intracardiac procedures, TEE may be used.For noncardiac surgery patients, studies with observational findings or case reports note the detection of the following abnormalities by TEE: (1) venous air embolism and patent foramen ovale in neurosurgery (Category B2 evidence ); (2) pericardial effusion and compression of the cardiac chambers in liver transplantation (Category B3 evidence ); (3) intracardiac emboli and patent foramen ovale (Category B2 evidence ), mitral regurgitation, left ventricular hypertrophy, and left ventricular outflow tract obstruction in orthopedic surgery (Category B3 evidence ), (4) left ventricular segmental wall motion abnormalities (Category B2 evidence ), aortic lesions and atrial tumors in vascular surgery (Category B3 evidence ), and (5) atrial septal defect, myocardial ischemia, hypovolemia, pericardial tamponade, thromboembolic events (Category B2 evidence ), pericardial effusion, tamponade, and intrapulmonary emboli in other major surgery (i.e. , lung, renal, abdominal, and head/neck/chest wall surgeries) (Category B3 evidence ).The consultants and ASA members agree that TEE should be used for noncardiac surgical patients when the patient has known or suspected cardiovascular pathology that might result in hemodynamic, pulmonary, or neurologic compromise. The consultants and ASA members both strongly agree that TEE should be used during unexplained persistent hypotension. Further, both the consultants and ASA members agree that TEE should be used when persistent unexplained hypoxemia occurs. The ASA members agree and the consultants strongly agree that TEE should be used when life-threatening hypotension is anticipated.Both the consultants and ASA members agree that TEE should be used during either lung transplantation or major abdominal or thoracic trauma. The consultants agree although the ASA members are equivocal regarding the use of TEE during open abdominal aortic procedures and liver transplantation. Both the consultants and ASA members are equivocal regarding the use of TEE during: (1) endovascular aortic procedures, (2) neurosurgery in the sitting position, and (3) percutaneous cardiovascular interventions (e.g. , femoral artery stenting). Finally, the consultants and ASA members both disagree with the assertion that TEE should be used during orthopedic surgery.TEE may be used when the nature of the planned surgery or the patient's known or suspected cardiovascular pathology might result in severe hemodynamic, pulmonary, or neurologic compromise. If equipment and expertise are available, TEE should be used when unexplained life-threatening circulatory instability persists despite corrective therapy.Studies with observational findings for critically ill patients with an unexplained adverse postoperative clinical course report TEE detection for the following abnormalities: regurgitant valvular lesions, aortic or mitral valve vegetation, aortic dissection, intracardiac mass, tamponade, ventricular failure, and hypovolemia (Category B2 evidence ). Case reports of critically ill postoperative patients indicate that TEE detects abnormalities such as aortic root abscess, pericardial hematoma, atherosclerotic debris in the thoracic aorta, left ventricular hypertrophy, wall motion abnormalities, and ventricular masses (Category B3 evidence ).Both the consultants and ASA members strongly agree that TEE should be used for critical care patients when diagnostic information expected to alter management cannot be obtained by transthoracic echocardiography or other modalities in a timely manner. The ASA members agree and the consultants strongly agree that TEE should be used during unexplained persistent hypotension. They both agree that TEE should be used when persistent unexplained hypoxemia occurs.For critical care patients, TEE should be used when diagnostic information that is expected to alter management cannot be obtained by transthoracic echocardiography or other modalities in a timely manner.Studies with observational findings and case reports indicate that, although rare, potential complications associated with TEE may include esophageal perforation, esophageal injury, hematoma, laryngeal palsy, dysphagia, dental injury, or death (Category B2 evidence ). However, there is insufficient literature to assess whether there are contraindications for the use of TEE (Category D evidence ).Both the consultants and ASA members are equivocal with regard to whether there are no absolute contraindications to TEE other than previous esophagectomy or esophagogastrectomy. Those consultants and ASA members who do not agree that there are no absolute contraindications other than previous esophagectomy or esophagogastrectomy do agree that the following four conditions should be absolute contraindications to TEE: esophageal stricture, tracheoesophageal fistula, postesophageal surgery, and esophageal trauma. Both the consultants and ASA members disagree that the following four conditions should be absolute contraindications to TEE: Barrett esophagus, hiatal hernia, large descending aortic aneurysm, and unilateral vocal cord paralysis. Finally, both the consultants and ASA members are equivocal with regard to whether the following three conditions should be absolute contraindications to TEE: esophageal varices, postradiation therapy, and previous bariatric surgery. The consultants agree but the ASA members are equivocal that Zenker diverticulum and colonic interposition are absolute contraindications. Finally, the ASA members disagree and the consultants are equivocal that dysphagia is an absolute contraindication to TEE.TEE may be used for patients with oral, esophageal, or gastric disease, if the expected benefit outweighs the potential risk, provided the appropriate precautions are applied. These precautions may include the following: considering other imaging modalities (e.g. , epicardial echocardiography), obtaining a gastroenterology consultation using a smaller probe, limiting the examination, avoiding unnecessary probe manipulation, and using the most experienced operator.For these Guidelines, a literature review was used in combination with opinions obtained from expert consultants and other sources (e.g. , ASA members, open forums, Internet postings). Both the literature review and opinion data were based on evidence linkages or statements regarding potential relationships between clinical interventions and outcomes. The efficacy and outcomes from the use of TEE were examined for the following procedures:The impact of the use of perioperative TEE was assessed on the basis of the following:For the literature review, potentially relevant clinical studies published after 1994 were identified via electronic and manual searches of the literature. The electronic and manual searches covered a 16-yr period from 1994 through 2009. More than 8000 citations were initially identified, yielding a total of 861 nonoverlapping articles that addressed topics related to the evidence linkages. After review of the articles, 404 studies did not provide direct evidence and were subsequently eliminated. A total of 457 articles contained direct linkage-related evidence. A complete bibliography used to develop these Guidelines, organized by section, is available as Supplemental Digital Content 2, http://links.lww.com/ALN/A568.Literature reporting the detection of new abnormalities by TEE was summarized, followed by a summary of literature reporting the confirmation of previously diagnosed abnormalities by TEE. The sensitivity, specificity, and positive and negative predictive values for the efficacy of TEE in detecting new abnormalities and in confirming or redefining previous diagnoses were also obtained (table 1). Study findings reporting the misdiagnosis or limited effectiveness of TEE to detect pathology are also listed in table 1.Interobserver agreement among Task Force members and two methodologists was established by interrater reliability testing. Agreement levels using a κ statistic for two-rater agreement pairs were as follows: (1) type of study design, κ= 0.50–1.00; (2) type of analysis, κ= 0.50–0.83; (3) evidence linkage assignment, κ= 0.75–1.00; and (4) literature inclusion for database, κ= 0.78–1.00. Three-rater chance-corrected agreement values were as follows: (1) study design, Sav = 0.66, Var (Sav) = 0.006; (2) type of analysis, Sav = 0.66, Var (Sav) = 0.007; (3) linkage assignment, Sav = 0.83, Var (Sav) = 0.005; and (4) literature database inclusion, Sav = 0.84, Var (Sav) = 0.046. These values represent moderate to high levels of agreement.Consensus was obtained from multiple sources, including (1) survey opinion from consultants who were selected based on their knowledge or expertise in the perioperative use of TEE, (2) survey opinions solicited from active members of the ASA who personally perform TEE as part of their practice, (3) testimony from attendees of a publicly held open forum at an international anesthesia meeting, (4) Internet commentary, and (5) Task Force opinion and interpretation. The survey rate of return was 53% (n = 55 of 103) for the consultants, and 818 surveys were received from active ASA members who indicated that they personally performed TEE as part of their practice. Results of the surveys are reported in tables 2 and 3and summarized in the text of the Guidelines.The consultants were asked to indicate which, if any, of the recommendations would change their clinical practices if the Guidelines were instituted. The rate of return was 14% (n = 14 of 103). The percent of responding consultants expecting a change in their practice associated with each linkage topic was as follows: (1) major cardiac and thoracic aortic surgery, 7%; (2) transcatheter intracardiac procedures, 0%; (3) pacemaker and implanted cardioverter defibrillator lead extraction, 7% (4); neurosurgery, 7% (5); liver transplantation, 0% (6); orthopedic surgery, 7% (7); vascular/endovascular surgery, 7%, (8) other major surgery (i.e. , lung, renal, abdominal, and head/neck/chest wall), 14%; and (9) postoperative critical care, 21%. Eighty-six percent indicated that their clinical practice will not need new equipment, supplies, or training to implement the Practice Guidelines. Eighty-six percent indicated that the Guidelines would not require ongoing changes in their practice which will affect costs. One hundred percent of the respondents indicated that the Guidelines would have no effect on the amount of time spent on a typical case.